Reducing fracture risk in damaged aluminum plates: Finite element evaluation of bonded, riveted, and hybrid patches

In this study, a three-dimensional finite element analysis was performed to compare bonded, riveted, and hybrid bonded-riveted patch repairs applied to a notched 2024-T3 aluminum plate under tensile loading. The repair efficiency was evaluated using the J-integral and the peak stresses for different crack lengths (a), patch materials, and rivet layouts. The results showed that all repair strategies significantly reduced the J-integral compared with the unrepaired plate. For the lengthiest crack, the bonded patch reduced the J-integral by more than 86%. For riveted and hybrid repairs, the fastener layout had a decisive effect on the mechanical response. For short cracks, most rivet layouts provided comparable reinforcement, whereas for lengthier cracks, rivets located along the crack propagation path increased local stress concentration and reduced repair efficiency. Among the investigated layouts, a 10-rivet layout provided the most favorable stress redistribution, by reducing the J-integral by about 16−30% compared with unfavorable layouts aligned with the crack path. In hybrid repairs, the adhesive layer promoted distributed load transfer, while the rivets contributed to global joint integrity. These results show that repair performance is governed by the coupled effects of patch material, a value, adhesive load transfer, and rivet spatial distribution.